removed today, and just to show what ive said before, sylvainia sons are absolute crap, they all go the same way, the glass gets this rough etched in white power eating into the glass, makes you shiver when you touch them, note the philips lamp on the end, also failed, well cycling, philips never go the way sylvainia lamps go, they allways remain clear to the end, just slight blackening, some go completly black i know, but 9 times out of 10 they look virtually as new when removed

How many years on them though?

dont know exactly, prob about 5, the philips is the same age

They are a bit rough for 5!

Theyre 100s though your lucky if any brand of 100w lasts more then 3-4 years.

yes, they do have the worst life, why is that? and 50's, they are poor too

Cos the arc tubes in these are just 70w arc tubes. So putting them on 100 gear seems to halve the life. Pulling out 2013 and 14 philips here now

50s im not sure maybe the ballasts are just 70w but printed 50w. 4-5 year out of these id say isnot bad especially for 100w

didnt know 100 watt sons had 70 watt arc tubes in them, thats ok then as ive bodged 100 watt son ballasts in 70 watt lanterns to get em going in the past, and they seem to work fine lol

I do find it strange how these get that white coating on the outer jacket, the modern Osrams do the same, although id say these 100w are better than Philips ones as i was pulling 2008 ones out when i was with the street lighting lads.. Think i gave some to Dan

You can also run the 100w lamp off a 70w ballast cos then in theory its just a e40 70w lamp

A couple of those look quite well fried
The white powder thing sounds weird.